The next year’s iPhone iteration, unofficially dubbed “iPhone 6,” may come with at least two bigger screen sizes -- 4.7-inch and 5.7-inch -- as Apple is mulling over expanding its flagship smartphone range, Reuters reported, citing “four people with knowledge of the matter” and sources in the Apple supply chain in Asia.

The report said suppliers have already showed their plans for the bigger screens to Apple, but nothing has been finalized yet as the move is still under discussion.

In addition, Apple is also known for frequently altering specifications of a yet-to-be-released product till the final moment of letting it out for a public release. Therefore, it’s still not clear if the bigger iPhone models in question are the final prototypes.

Whether Apple decides to launch the iPhone 6 with a bigger screen or not, the company is surely under pressure as rival Samsung has surpassed it in global smartphone market share. Critics have also said that Apple’s pace of innovation has slowed down in the post-Steve Jobs era.

With the launch of iPhone 5 in 2012, Apple ditched the traditional 3.5-inch screen and increased the phone’s screen size to 4 inches. However, the screen size of iPhone 5 is still considered to be small as many other Android smartphones in the market feature screens that measure up to 6.3 inches.

Samsung’s latest Galaxy S4 features 5-inch screen and the Galaxy Note 2 has an even bigger 5.5-inch screen. The company recently announced a new handset, dubbed “Galaxy Mega,” with a massive 6.3-inch display.

Jefferies analyst Peter Misek said in April that Apple would launch the iPhone 6 with a bigger display in June 2014. Misek said that although Apple is getting the supply chain ready for the handset, it will take at least two or three quarters to develop and manufacture the device.

The rumor contradicts CEO Tim Cook’s recent statement during Apple’s Q2 2013 earnings call in April, saying that the company would not consider launching iPhone models with a larger screen at present because of “tradeoffs” in other aspects like resolution, color quality, brightness, reflectivity and screen longevity among others.

As for this year’s iPhone offerings, Apple is expected to release two versions of the handset -- the iPhone 5S, the 2013 flagship model with fingerprint sensor technology and a low-cost version of the iPhone in plastic casing, Reuters reported.

The iPhone 5S will be available in black and white, while the less expensive version will come in a range of five to six colors. The price of iPhone 5S is still unknown, but Apple is said to have discussed a $99 price point for the cheaper model. It’s not clear whether the rumored price is a carrier-subsidized cost or the actual price of the device without a contract.